The scrap delivery service requires specially designed pallet carriers to transport loaded scrap baskets to the furnace. These machines are required to traverse one-half mile (1km) over a partially paved, slag road with a 400K lbs. (183 tonnes) payload. To achieve the load capacity, extremely high tire pressures would have been required for each of the twelve rear tires. However, operational space limitations did not allow for additional wheels or axles to disperse the load to reduce the air pressures required. This posed a very real safety risk for pallet carrier operators and nearby site workers, as the machines must navigate road hazards like potholes, scrap metal, ruts and debris. With the proximity of the tires, if one tire were to explode, the rest would follow.